Regarding pain in breast. Fibroadenosis?

Helo mam/sir I m having pain in my right breast. Actualy i cant exactly determine the pain in the breast or beneath the breast.bt when i press my breast i dont feel paun. Mild pain is always there i feel it actualy when i take deep breath or lift something heavy. Earlier I used to go to gym n lift weigt also. Bt due to pain frm approx 3months i have left. I ahve consultd a physcian n having some medicines with the hlp of medicines the pain is less. X ray report ws norml.the dr. Said it must be muscular pain. I am little bit afraid so i optd for sonomamogrphy in its report mild bilateral fibroadenosis are found. Is it anythng serious.? The pain is due to muscles or this Mild fibroadenosis? Plz suggest what should i do...